4. 3 2 4· 7 4 5 3 3 0 p i Γ. d ο c / Ο 〇 2 A? _______B7_____ 五、發明說明（i ) 發明領域 本發明是有關於一種重覆且步進（step-and-repeat)或掃 瞄且步進（step-and-scan)之曝光裝置，且特別是有關於一 種在製作半導體元件或液晶元件的曝光裝置中，用以控制 基底與光學系統之間距離的對焦（focussing)與水平校正 (levelling)之對焦方法及系統。 背景說明 · 在一般的曝光裝置中，諸如罩幕（mask)或光罩（reticle) 等製作母板（master plate)上的電路圖案，是被製作於半導 體晶圓的光阻層上’經顯影後以獲得所需之光阻圖案。 在一般半導體元件的製程中，通常需要在基底上疊覆 數層至數十層電路圖案’因此’必須使欲曝光之電路圖案 的影像’與晶圓上已形成之電路圖案對準。爲了進行圖案 化’對於確保光學系統中縮小的投影透鏡至晶片表面之間 固定的焦距（即”對焦”）’以及確保聚焦於特定區域（“即水 平校正”)而Η ’曝光裝置是非常重要的。傳統上，具有廣 大面積的光源可用以確保水平校正，然而近來，亦可以水 平校正控制系統來確認兩個焦距或兩個以上的焦距。 在最近的半導體技術中，半導體元件需提高其積集 度，就記憶體與非記憶體的領域而言，堆疊結構已常被用 於提高其積集度。當積集度增加時，堆疊結構亦隨之變得 複雜。在製作具有複雜之堆疊結構的半導體積體電路時， 曝光裝置必須能夠克服製作複雜之堆疊結構，以及於進行 圖案化時的困難’使其仍具有相同的焦距。若曝光裝置在 4 ' 本紙張尺度適用中國國家標準（CNS)A4規格（210 x'297公釐） 經濟部智慧財產局員工消費合作社印製 4 3 24： 7 4 5 33〇pildoc/002 pj 五、發明說明（^ ) 定義圖案時’分別具有不同的焦距，則會形成偏差的圖案， 導致無法進行半導體元件之製作。用以製作具有堆疊結構 之半導體元件的曝光裝置，係採用一種對焦系統，藉由電 容器或雷射對晶圓表面進行對焦。 第1A圖及第1B圖係用以說明習知對焦方法及系統 的問題之示意圖。 請參照第1A圖及第1B圖，其中傳統的對焦系統200 可確認兩個焦距或兩個以上的焦距，而且還至少具有兩個 發光元件210及220，以及兩個光接收元件216和226。 由傳統的發光元件21〇及220所產生之第一入射光212和 第二入射光222，其入射角約爲45度至60度，且第一入 射光212與第二入射光222之穿透率爲80%或80%以上。 此種傳統的對焦系統是藉偵測分別由第一材料層254與第 二材料層256所反射之第一反射光2 14和第二反射光224， 來控制半導體晶圓250與光學系統（未顯示於圖中）之間的 對焦和水平校正，以進行曝光製程，其中第一材料層254 及第二材料層256係堆疊於半導體晶圓250所構成之基底 252上。第一反射光214與第二反射光224係穿透半導體 晶圓250上的光阻層258，再分別由第二材料層256及第 一材料層254反射形成。此時，由於第一材料層254與第 二材料層256之間具有高度差，因此在確認其焦距時，比 較經由第一材料層254反射形成的第二反射光224與第一 反射光214，兩者的光程差爲”A”。如第6B圖所示，在傳 統的對焦系統200中，藉由控制半導體晶圚250之位置， 5 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） -----l·---*--裝--------訂--------- (請先閲讀背面之注意事項再填寫本頁) 5 33 0 pil'.doc/002 A7 B7 五、發明說明（> ) 以解決第一反射光束2I4與第二反射光束224之間光程差 所造成的問題。然而，此舉將導致水平校正不正確的結果。 在傳統的對焦方法與系統中，反射光係穿透光阻層， 再經由位於光阻層下，諸如金屬層或多晶砂層構成之反射 層所反射而形成，藉由偵測反射光來控制對焦及水平校 正。但是，這種方法及系統會造成水平校正錯誤（亦即無 法於固定區域進行正確對焦）。 此外，在傳統的對焦方法及系統中 > 並無法獲得適當 的聚焦位置。這是因爲由光阻層258表面反射形成的反射 光（未顯示於圖中）被視爲雜訊，進而影響反射光214及 224 ° 在傳統的對焦方法和系統中，在製作複雜的堆疊結構 時，其所進行之步驟將會產生偏差的圖案。尤其是藉由雷 射確認兩個焦距或兩個以上之焦距的對焦系統，由於在特 定區域內無法得到相同的焦距，導致量測到不對稱或不正 確的焦距，所以在製作堆疊結構時會發生問題。因此，在 對特定區域進行曝光時，會產生散焦（defocus)現象，形成 偏差的圖案。 經濟部智慧財產局員工消費合作社印製 (請先閱讀背面之注意事項再填寫本頁) 發明之槪述 本發明的其中一個目的就是在提供一種對焦方法及系 統，可在製作半導體元件或液晶元件的曝光裝置中，對置 於曝光裝置中且具有複雜堆疊結構的半導體晶圓，可以進 行穩定地對焦及水平校正。 本發明的另一目的就是在提供一種對焦方法及系統， 6 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐) "" 432474 5330pirdoc/002 A7 B7 經濟部智慧財產局員工消費合作社印製 五、發明說明（f ) 在藉由雷射以確認兩個焦距的對焦系統中’可以確保對於 具有堆疊結構之半導體晶圓上特定區域而言’具有單一的 焦距。 根據本發明之特徵，提出一種控制曝光裝置中光學系 統與基底兩者距離，用以將基底表面圖案化的方法，·其中 在基底上具有鍍層，鍍層上則具有一個表面。在此種方法 中包括：以特定入射角發射光束，使其在光阻層表面之反 射光的強度大於穿透光；偵測由基底上之光阻層表面所反 射之光束；以及控制基底與被偵測之反射光兩者的相對位 置，藉以在基底表面之特定區域，獲得單一的焦距= 在本發明之實施例中，光束之入射角約大於或等於一 個特定角度，使得垂直入射於光阻層表面之入射光分量的 反射率高於其穿透率。 在本發明之實施例中，光束之入射角約大於或等於一 個特定角度，使得水平入射於光阻層表面之入射光分量的 反射率高於其穿透率。 根據本發明之另一特徵，於曝光裝置中對具有堆疊結 構之半導體晶圓與光阻層之表面進行曝光製程時，在用以 確認兩個焦距或兩個以上之焦距的對焦系統中，包括有： 產生光束用以偵測對於半導體晶圓之焦距的光源單元，而 且光源單元可以特定入射角發射光東，使其在光阻層表面 之反射光的強度大於穿透光；而用以偵測反射光的偵測單 元，在其偵測到反射光時會產生偵測訊號；以及根據偵測 單元所產生之偵測訊號以調整半導體晶圓位置的控制單 請 先 閱 讀 背 意 事 項, 填 寫裝 頁 訂 本紙張尺度適用中國國家標準<CNS)A4規格（210 X 297公釐） 經濟部智慧財產局員工消費合作社印製 4324 7 4 ?330pir.doc/0U2 ' pj B7 五、發明說明（义） 元，藉此可以確認兩個焦距或兩個以上的焦距，並且可以 控制使其對半導體晶圓之特定區域具有一個特定焦距。 在本發明之對焦方法及系統中，量測焦距使用之光束 是以特定入射角照射至具有高反射率的晶圓，而經由半導 體晶圓上的光阻層表面反射之反射光則會被偵測到，·藉此 以控制其間之焦距。由於對半導體晶圓上複雜的堆疊結構 可以維持其間的焦距，在曝光製程中可以防止對焦不良及 水平校正不佳的產生，因此可以確保進行良好的圖案化製 程。尤其是在藉由雷射確認兩個焦距或兩個以上之焦距的 對焦系統中，對位於其中且具有堆疊結構之半導體晶圓上 的特定區域而言，可以確保其具有相同的焦距。 圖式之簡單說明: 爲讓本發明之上述和其他目的、特徵、和優點能更明 顯易懂，下文特舉較佳實施例，並配合所附圖式，作詳細 說明如下： 第1A圖與第1B圖所繪示舄習知對焦方法及系統的 問題之示意圖； 第2圖所繪示爲依照本發明之實施例，一種對焦系統 之結構示意圖； 第3圖所繪示爲依照本發明之一種對焦方法，其在具 有不同折射率的兩種介質中之光程的示意圖； 第4A圖所繪示爲第2圖中垂直入射至兩介質之界面 的入射光分量’其反射率與穿透率之間的關係示意圖； 第4B圖所繪示爲第2圖中水平入射至兩介質之界面4. 3 2 4 · 7 4 5 3 3 0 pi Γ. D ο c / 〇 〇2 A? _______B7_____ V. Description of the invention (i) Field of the invention The present invention relates to a step-and- repeat) or step-and-scan exposure device, and in particular, it relates to a focus (for controlling the distance between a substrate and an optical system in an exposure device for manufacturing a semiconductor element or a liquid crystal element) focussing) and levelling (focusing method) and system. Background · In a typical exposure device, a circuit pattern on a master plate, such as a mask or reticle, is produced on the photoresist layer of a semiconductor wafer. And obtain the desired photoresist pattern. In the general semiconductor device manufacturing process, several layers to tens of layers of circuit patterns are usually superimposed on the substrate. Therefore, the image of the circuit pattern to be exposed must be aligned with the circuit pattern already formed on the wafer. In order to pattern 'for ensuring a fixed focal distance between the reduced projection lens in the optical system and the surface of the wafer (ie, "focus") "and to ensure focus on a specific area (" horizontal correction "), Η' exposure device is very important of. Traditionally, a light source with a large area can be used to ensure horizontal correction. Recently, however, a horizontal correction control system can also be used to confirm two or more focal lengths. In the recent semiconductor technology, semiconductor elements need to increase their accumulation level. In terms of memory and non-memory fields, stacked structures have been often used to increase their accumulation level. As the degree of accumulation increases, the stacking structure becomes more complicated. When fabricating a semiconductor integrated circuit with a complex stack structure, the exposure device must be able to overcome the difficulties of making a complex stack structure and patterning 'so that it still has the same focal length. If the exposure device is at 4 ', this paper size is in accordance with China National Standard (CNS) A4 (210 x'297 mm). Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 4 3 24: 7 4 5 33〇pildoc / 002 pj 5 2. Description of the invention (^) When the pattern is defined, if the respective focal lengths have different focal lengths, a misaligned pattern will be formed, making it impossible to manufacture a semiconductor device. The exposure device used to make semiconductor elements with a stacked structure uses a focusing system to focus the surface of the wafer by a capacitor or laser. 1A and 1B are schematic diagrams for explaining problems of the conventional focusing method and system. Please refer to FIG. 1A and FIG. 1B, where the conventional focusing system 200 can confirm two or more focal lengths, and further has at least two light emitting elements 210 and 220, and two light receiving elements 216 and 226. The incident angles of the first incident light 212 and the second incident light 222 generated by the conventional light emitting elements 21 and 220 are about 45 to 60 degrees, and the first incident light 212 and the second incident light 222 penetrate The rate is 80% or more. This conventional focusing system controls the semiconductor wafer 250 and the optical system (not shown) by detecting the first reflected light 214 and the second reflected light 224 reflected by the first material layer 254 and the second material layer 256, respectively. (Shown in the figure) for focusing and level correction to perform the exposure process. The first material layer 254 and the second material layer 256 are stacked on a substrate 252 formed by a semiconductor wafer 250. The first reflected light 214 and the second reflected light 224 pass through the photoresist layer 258 on the semiconductor wafer 250, and are formed by being reflected by the second material layer 256 and the first material layer 254, respectively. At this time, since there is a height difference between the first material layer 254 and the second material layer 256, when confirming the focal length thereof, the second reflected light 224 and the first reflected light 214 formed through the reflection of the first material layer 254 are compared. The optical path difference between the two is "A". As shown in Figure 6B, in the conventional focusing system 200, by controlling the position of the semiconductor wafer 250, 5 paper sizes are applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) ----- l · --- *-install -------- order --------- (Please read the notes on the back before filling this page) 5 33 0 pil'.doc / 002 A7 B7 V. Description of the Invention (>) To solve the problem caused by the optical path difference between the first reflected light beam 2I4 and the second reflected light beam 224. However, this will lead to incorrect results in level correction. In traditional focusing methods and systems, the reflected light penetrates the photoresist layer, and is formed by reflecting under the photoresist layer, such as a metal layer or a polycrystalline sand layer, and is controlled by detecting the reflected light. Focus and level correction. However, this method and system will cause horizontal correction errors (that is, it is impossible to focus correctly on a fixed area). In addition, in conventional focusing methods and systems > it is not possible to obtain a proper focusing position. This is because the reflected light (not shown in the figure) formed by the reflection of the surface of the photoresist layer 258 is regarded as noise, which affects the reflected light 214 and 224 ° In the traditional focusing method and system, in the production of complex stacked structures As a result, the steps performed will produce a deviating pattern. In particular, a focusing system that confirms two or more focal lengths with a laser, because the same focal length cannot be obtained in a specific area, leading to measurement of asymmetric or incorrect focal lengths, so when making a stacked structure, Something went wrong. Therefore, when a specific area is exposed, a defocus phenomenon occurs, and a deviated pattern is formed. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs (please read the precautions on the back before filling out this page) Description of the invention One of the purposes of the present invention is to provide a focusing method and system that can be used to produce semiconductor elements or liquid crystal elements In an exposure device of the type, a semiconductor wafer having a complex stack structure placed in the exposure device can perform stable focusing and level correction. Another object of the present invention is to provide a focusing method and system. 6 paper sizes are applicable to China National Standard (CNS) A4 (210 X 297 mm) " " 432474 5330pirdoc / 002 A7 B7 Intellectual Property Bureau, Ministry of Economic Affairs Printed by the Staff Consumer Cooperatives V. Description of the Invention (f) In the focusing system that confirms the two focal lengths by laser, 'it can ensure a single focal length for a specific area on a semiconductor wafer with a stacked structure'. According to a feature of the present invention, a method for controlling the distance between an optical system and a substrate in an exposure device for patterning the surface of the substrate is proposed, wherein a plating layer is provided on the substrate, and a surface is provided on the plating layer. The method includes: emitting a light beam at a specific angle of incidence so that the intensity of the reflected light on the surface of the photoresist layer is greater than the transmitted light; detecting the light beam reflected by the surface of the photoresist layer on the substrate; and controlling the substrate and The relative position of the detected reflected light to obtain a single focal length in a specific area of the substrate surface = In the embodiment of the present invention, the incident angle of the light beam is approximately greater than or equal to a specific angle, so that the incident light is perpendicular to the light. The reflectivity of the incident light component on the surface of the resist is higher than its transmittance. In the embodiment of the present invention, the incident angle of the light beam is approximately greater than or equal to a specific angle, so that the reflectance of the incident light component incident horizontally on the surface of the photoresist layer is higher than its transmittance. According to another feature of the present invention, when an exposure process is performed on the surface of a semiconductor wafer having a stacked structure and a photoresist layer in an exposure device, a focusing system for confirming two or more focal lengths includes There are: a light source unit that generates a light beam to detect the focal length of a semiconductor wafer, and the light source unit can emit light at a specific incident angle so that the intensity of the reflected light on the surface of the photoresist layer is greater than the transmitted light; The detection unit for measuring reflected light will generate a detection signal when it detects the reflected light; and a control sheet for adjusting the position of the semiconductor wafer according to the detection signal generated by the detection unit. Please read the note first, fill in The paper size of the bound book applies to the Chinese National Standard < CNS) A4 specification (210 X 297 mm) printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economy 4324 7 4? 330pir.doc / 0U2 'pj B7 V. Description of the invention ( It can confirm two focal lengths or more, and control it to have a specific focal length for a specific area of a semiconductor wafer. In the focusing method and system of the present invention, the beam used for measuring the focal length is irradiated to a wafer with high reflectance at a specific incident angle, and the reflected light reflected by the surface of the photoresist layer on the semiconductor wafer is detected To, · Take this to control the focal distance between them. Because the complex stack structure on the semiconductor wafer can maintain the focal distance therebetween, it can prevent the occurrence of poor focus and poor level correction during the exposure process, so it can ensure a good patterning process. Especially in a focusing system that confirms two or more focal lengths by laser, for a specific area on a semiconductor wafer having a stacked structure therein, it can be ensured that they have the same focal length. Brief description of the drawings: In order to make the above and other objects, features, and advantages of the present invention more comprehensible, the following describes the preferred embodiments in detail with the accompanying drawings, as follows: Figure 1A and FIG. 1B is a schematic diagram of a problem with a conventional focusing method and system; FIG. 2 is a schematic diagram of a focusing system according to an embodiment of the present invention; and FIG. 3 is a schematic diagram of a focusing system according to the present invention. A focusing method with schematic diagrams of the optical paths in two media with different refractive indices; FIG. 4A shows the incident light component of FIG. 2 perpendicular to the interface of the two media, its reflectance and penetration Schematic diagram of the relationship between rates; Figure 4B shows the interface between two media incident horizontally in Figure 2
S 本紙張尺度適用+國國家標準（CNS)A4規格（210 X 297公釐） — — — — — — l· — !! — I (請先閱讀背面之注意事項^:填寫本頁) 訂， 經濟部智慧財產局員工消費合作社印製 432474 -Vl30pi I'.doc/O02 A7 __B7_ 五、發明說明（b) 的入射光分量，其反射率與穿透率之間的關係示意圖； 第5圖所繪示爲在依照本發明之對焦方法及系統中， 用以量測焦距之光程的示意圖；以及 第6A圖與第6B圖所繪示爲依照本發明之實施例， 在藉由雷射確認兩個焦距或兩個以上之焦距的對焦系統 中，用以確認半導體晶圓焦距及其狀態之方法的示意圖。 圖式之標記說明： 10、200 :對焦系統 12、14、210、220 :發光元件 16、18 ' 216、226 :光接收元件 19、19’ ：控制器 20 :訊號處理器 22 :載台控制器 24 :載台 26、250 :半導體晶圓 28 :光學系統 30 :低折射率介質 32 :高折射率介質 34 :界面 38、80、84、212、222 :入射光 40、80、86、214、224、228 :反射光 42 :穿透光 44、90、92 :入射角 46 :穿透角 9 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） -----L-----' J 裝--------訂 -------- (請先閱讀背面之注意事項#填寫本頁) 43 24 7 4 5 33 Opi t'.doc/0 0 2 pj _B7_ 五、發明說明（1 ) (請先閱讀背面之注意事項再填寫本頁) 50、60 :反射率 52、62 :穿透率 70、252 :基底 72、254 :第一材料層 74、256 :第二材料層 - 76、258 :光阻層 100、102、104、110、Π2、1 14、1 16 :焦距 “A” ：光程差 較佳實施例之詳細說明 以下將以本發明之較佳實施例，並配合所附圖式加以 詳細說明，而圖式中相同之標號係代表相同之元件件。 第2圖其所繪示的是依照本發明之實施例，一種用於 曝光裝置的對焦系統，其結構之示意圖。 經濟部智慧財產局員工消費合作社印製 請參照第2圖，本發明之對焦系統10係配置於曝光 裝置中，且可以使用電容器及雷射。在本實施例中，對焦 系統10係使用雷射確認兩個焦距或兩個以上之焦距，而 光學系統28與載台24之間的距離則由對焦系統10控制。 置於載台24上之半導體晶圓26的表面覆有光阻層，光學 系統28是用以對光阻層進行曝光，將所需之圖案轉移至 光阻層。對焦系統10是用以控制曝光裝置之對焦與水平 校正，使其得以進行曝光製程。 一般而言，對焦系統10中包括有光源單元、偵測單 元以及控制單元，而光源單元中則包括有第一發光元件 〗2、第二發光元件14,以及控制器19,當然在光源單元 本紙張尺度適用中國國家標準（CNS)A4規格（210 * 297公釐） 經濟部智慧財產局員工消費合作杜印製 432Λ7 4 ? 3 3 0pi f.doo/O0 2 pj 五、發明說明（） 中，亦可以配置複數個發光源用以發出光束。而第一發光 元件12與第二發光元件14可以採用可變方式進行配置， 例如可以調整其光束之入射角。由第一發光元件12及第 二發光元件14所產生之偏向光束，可以垂直入射至半導 體晶圓26之入射表面，而且藉由控制器19可以自動調整 第一發光元件12和第二發光元件14。在偵測單元中具有 分別對應於第一發光元件12與第二發光元件14之第一光 接收元件16和第二光接收元件18，此外還有訊號處理器 20以及控制器19’。第一光接收元件16、第二光接收元件 18與第一發光元件12、第二發光元件14類似，是由控制 器19’所控制以進行自動調整。由於發光元件12、14是與 光接收元件16、18彼此相互關連，所以控制器19和19’ 亦可以彼此連鎖，或者是作爲單一控制器來使用。 雖然在後續的詳細說明中，當半導體晶圓26處於停 頓狀態時，本發明之對焦系統10使用三個發光元件及三 個光接收元件進行對焦。而另一方面，當半導體晶圓26 處於移動狀態時，則使用四個發光元件與四個光接收元件 進行對焦。 由第一發光元件12及第二發¥元件14所產生的光 束，經由位於載台24上的半導體晶圓26反射後，被傳送 至第一光接收元件16和第二光接收元件18。若第一光接 收元件16和第二光接收元件18所偵測到光束，偵測單元 中的訊號處理器20則會輸出一個焦距量，並將這個焦距 量傳送到控制單元。控制單元中具有載台24與載台控制 本紙張尺度適用中國國家標準（CNS>A4規格（210 X 297公釐） (請先閲讀背面之注意事項再填寫本頁) ,θ. 裝 432474 5 3 3 Ο ρ ΐ 1', d o c / Π Ο 2 Α7 __Β7____ 五、發明說明（1 ) 器22 ’而載台控制器Μ依據來自訊號處理器2〇的訊號， 控制載台24之動量，藉以調制其焦距進行曝光製程。 第3圖、第4Α圖及第4Β圖所繪示的是依照本發明 之一種對焦方法及系統，分別用以描述其技術背景之示意 圖及其特性之曲線變化圖。 ‘ 經濟部智慧財產局員工消費合作杜印製 請參照第3圖 '第4Α圖及第4Β圖，當入射光38由 低折射率介質3 〇入射至高折射率介質3 2時，光束的穿透 角會小於入射角’此時穿透光42與反射光40的強度是取 決於入射光38的入射角。入射光38是經由介質30入射 至介質32’其中介質3〇的折射率設定約爲1.5，而穿透光 則會fT經介質3 2 ’如弟4 Α圖及第4 Β圖所示，基於兩介 質之間存在的界面34，由入射光38的兩個分量所分別產 生之反射率與穿透率關係圖。亦即當入射光被劃分成垂直 進入界面34之入射光分量與水平進入界面34之入射光分 量等兩個分量時，依據電磁波原理來分析這兩個入射光分 量在介質30和32中的特性’其反射率與穿透率之間的關 係如第4A圖與第4B圖所示。此處，第4A圖係繪示垂直 進入界面34之入射光分量的反射率5〇與穿透率52，第4B 圖則繪示水平進入界面34之入射光分量的反射率60與穿 透率62。 如第3圖、第4A圖及第4B圖所示，當入射角44約 爲75度或約大於"75度時，反射率50會高於穿透率52 ; 此外，當入射角44約爲80度或約大於80度時，則反射 率60會高於穿透率62。因此，當入射光38、之入射角44 本紙張尺度適用中國葶家標準（CNS)A4規格（210 X 297公釐） 432474 5 } 3 0 p i Γ. d ο c/() 02 pj _B7_ 五、發明說明（β ) (請先閱讀背面之注意事項再填寫本頁) 的範圍維持在約爲75度至90度時，入射光38的反射率 會高於其穿透率。如第5圖所示，在對焦系統10中|，入 射光80及84分別具有入射角90和92，可使垂直進入界 面之入射光分量與水平進入界面之入射光分量的反射率高 於穿透率。 · 經濟部智慧財產局員工消費合作社印製 請參照第5圖，依照本發明可確認兩個焦距或兩個以 上之焦距的對焦系統10，其中具有第一發光元件12與第 二發光元件14，第一入射光80和第二入射光84係分別由 第一發光元件12及第二發光元件14所產生，然後照射至 半導體晶圓26上。此時，電路係以堆疊方式建構於半導 體晶圓26上，其中第一材料層72與第二材料層74即是 以堆疊方式配置於半導體晶圓26之基底70上，光阻層76 係覆蓋於第一.材料層72與第二材料層74上，而第一材料 層72與第二材料層74之間則具有階梯狀構造。光束經由 半導體晶圓26上之光阻層76的表面反射，其所產生之第 一反射光82和第二反射光84是由對焦系統10進行調焦。 如前所述，分別具有入射角90及92的第一入射光80和 第二入射光84，可以使其反射率高於穿透率。而入射角如 及92可藉由改變第一發光元件12及第二發光元件、4之 角度加以設定，例如可以控制第一發光元件12及第二發 光元件14之角度，使其與半導體晶圓26之間呈任意所需 的角度1而第一發光元件12與第二發光元件14具有可變 型態之結構。舉例而言，可以設定第一發光元件12及第 二發光元件14，使得與其對應·之第一入射角90和第二入 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） 4324T4 ri330pi!'.diu:/〇02 幻 _ _____________ B7__I_ 五、發明說明（丨f ) 射角92被控制在角度約爲75度至9〇度的範圍。 第6A圖及第6B圖所繪示的是依照本發明之實施例， 一種在藉由雷射確認兩個焦距或兩個以上之焦距的對焦系 統中’用以確認半導體晶圓焦距及其狀態之方法的示意 圖。 · 請參照第6A圖與第圖，依照本發明之實施例， 在藉由雷射確認兩個焦距或兩個以上之焦距的對焦系統 中’具有兩個焦距或兩個以上之焦距，而且在晶圓之特定 區域中具有單一的焦距（換言之，即是水平校正）。在進行 曝光製程時’半導體晶圓26可以是在停頓狀態（如第6A 圖所示）或掃瞄狀態（如第6B圖所示）下進行曝光，此外， 由於半導體晶圓26是沿著X、Y及z軸及轉動軸移動， 以進行對焦與水平校正，因此需要使焦距維持在同—平面 上’以獲得正確的水平校正。 經濟部智慧財產局員工消費合作社印製 如第6A圖所示’當半導體晶圓26處於停頓狀態時， 其具有三個焦距100、102及UM，而且具有三個焦距或者 三個以上之焦距是正常的。其中焦距1〇4係與其他兩個焦 距100及102垂直，而且確實位於半導體晶圓26上，因 此藉由焦距1〇〇、102及104等，可以獲得穩定的水平校 正。所以在前述之對焦系統中，光源單元（未顯示於圖中) 具有三個發光元件，而偵測單元（未顯示於圖中）中則具有 三個光接收元件，分別與前述之光源單元中的發光元件相 對應。 如第6B圖所示，當半導體晶圓26處於掃瞄狀態時， 本紙張尺度適用中國囷家標準（CNS)A4規格（210 X 297公釐） 經濟部智慧財產局員工消費合作社印製 432474 5 A7 五、發明說明（丨Z) 其具有四個焦距110、1丨2 ' 114及116，而且具有四個或 四個以上的焦距是正常的°其中焦距1丨4和116兩個焦距 是與其他兩個焦距Π0及II2垂直，而且也確實位於半導 體晶圓26上，所以藉由焦距U0、112、114及Π6等， 可以獲得穩定的水平校正。因此，在前述之對焦系統中， 光源單元（未顯示於圖中）具有四個發光元件，而偵測單元 (未顯示於圖中）中則具有四個光接收元件，分別與前述之 光源單元中的發光元件相對應。光源單元及偵測單元可以 分別具有複數個發光元件和複數個光接收元件’因此可以 根據需求來調整發光元件及光接收元件的數量。 本發明之對焦方法及系統，在特定之距離將入射光投 射至表面，使得入射光的反射率高於其穿透率。也就是可 以設定入射角，使得入射光之反射率闻於其穿透率的對焦 方法及系統。藉由本發明之對焦方法及系統’可獲得光阻 層表面之相關資訊，因此由偵測堆疊結構而得到不同的焦 距，可以縮減爲單一固定的焦距。在用以確認兩個焦距或 者兩個以上之焦距的校準系統中’用以將入射光傳導至半 導體晶圓的光阻層及空氣’由於其折射率之緣故，可使入 射角大於特定角度，所以可以確認兩個特定焦距或者兩個 以上的特定焦距。 應用本發明之對焦方法及系統’可以在具有複雜結構 的半導體晶圓上，維持固定的焦距。因此在進行曝光製程 時，可避免對焦不良及水平校正不丨圭的現象’以確保進行 良好的圖案化製程。尤其是在藉由雷射確認茸具有兩個焦 15 …..._____________________________- ^ 本紙張尺度適用令國固家標準（CNS)A4規格（210 X 297公楚） I l·— ϋ —r n 1 9— (請先閲讀背面之注意事項一^:填寫本頁) 'SJ__ 4 3 24 7 4 5.130pi j'.doc/(HJ2 pj _B7 五、發明說明（丨多） 距或者兩個以上之焦距的對焦系統中，對位於其中且具有 堆疊結構之半導體晶圓上的特定區域而言，可以確保其具 有相同的焦距。 雖然本發明已以較佳實施例揭露如上，然其並非用以 限定本發明，任何熟習此技藝者，在不脫離本發明之精神 和範圍內，當可作各種之更動與潤飾，因此本發明之保護 範圍當視後附之申請專利範圍所界定者爲準。 {請先閱讀背面之注意事項再填寫本頁) 裝 -'t/, 經濟部智慧財產局員工消費合作社印製 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐）S The size of this paper applies to the national standard (CNS) A4 specification (210 X 297 mm) — — — — — — l · — !! — I (Please read the notes on the back ^: Fill out this page first) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 432474 -Vl30pi I'.doc / O02 A7 __B7_ V. Description of the invention (b) The relationship between the reflectance and the transmittance of the incident light component is shown in Figure 5; It is shown as a schematic diagram for measuring the optical path of the focal length in the focusing method and system according to the present invention; and FIG. 6A and FIG. 6B are shown as an embodiment according to the present invention, and confirmed by laser A schematic diagram of a method for confirming the focal length of a semiconductor wafer and its state in a focusing system with two focal lengths or more. Description of drawing symbols: 10, 200: Focusing system 12, 14, 210, 220: Light-emitting elements 16, 18 '216, 226: Light-receiving elements 19, 19': Controller 20: Signal processor 22: Stage control Device 24: Stage 26, 250: Semiconductor wafer 28: Optical system 30: Low refractive index medium 32: High refractive index medium 34: Interface 38, 80, 84, 212, 222: Incident light 40, 80, 86, 214 , 224, 228: Reflected light 42: Penetrated light 44, 90, 92: Incident angle 46: Penetration angle 9 This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) ----- L ----- 'J Outfit -------- Order -------- (Please read the notes on the back first # Fill in this page) 43 24 7 4 5 33 Opi t'.doc / 0 0 2 pj _B7_ V. Description of the invention (1) (Please read the precautions on the back before filling out this page) 50, 60: Reflectance 52, 62: Transmittance 70, 252: Base 72, 254: First Material layers 74, 256: second material layers-76, 258: photoresist layers 100, 102, 104, 110, Π2, 1, 14, 1 16: focal length "A": detailed description of the preferred embodiment of the optical path difference is as follows The preferred embodiments of the present invention will be used in conjunction with the accompanying drawings For details, the same reference numerals in the drawings represent the same components. FIG. 2 is a schematic diagram showing the structure of a focusing system for an exposure device according to an embodiment of the present invention. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Please refer to Fig. 2. The focusing system 10 of the present invention is arranged in an exposure device, and capacitors and lasers can be used. In this embodiment, the focusing system 10 uses a laser to confirm two or more focal lengths, and the distance between the optical system 28 and the stage 24 is controlled by the focusing system 10. The surface of the semiconductor wafer 26 placed on the stage 24 is covered with a photoresist layer. The optical system 28 is used to expose the photoresist layer and transfer the required pattern to the photoresist layer. The focusing system 10 is used to control the focus and level correction of the exposure device so that it can perform the exposure process. Generally speaking, the focusing system 10 includes a light source unit, a detection unit, and a control unit, and the light source unit includes a first light emitting element 2, a second light emitting element 14, and a controller 19, of course, in the light source unit itself. Paper size applies to China National Standard (CNS) A4 (210 * 297 mm) DuPont printed by the Intellectual Property Bureau of the Ministry of Economic Affairs 432Λ7 4? 3 3 0pi f.doo / O0 2 pj 5. In the description of the invention (), Multiple light sources can also be configured to emit light beams. The first light-emitting element 12 and the second light-emitting element 14 can be arranged in a variable manner, for example, the incident angle of the light beam can be adjusted. The deflected light beams generated by the first light emitting element 12 and the second light emitting element 14 can be incident perpendicularly to the incident surface of the semiconductor wafer 26, and the controller 19 can automatically adjust the first light emitting element 12 and the second light emitting element 14 . The detection unit includes a first light-receiving element 16 and a second light-receiving element 18 corresponding to the first light-emitting element 12 and the second light-emitting element 14, respectively, and further includes a signal processor 20 and a controller 19 '. The first light receiving element 16 and the second light receiving element 18 are similar to the first light emitting element 12 and the second light emitting element 14 and are controlled by the controller 19 'for automatic adjustment. Since the light-emitting elements 12, 14 and the light-receiving elements 16, 18 are related to each other, the controllers 19 and 19 'can also be linked with each other or used as a single controller. Although in the subsequent detailed description, when the semiconductor wafer 26 is at a standstill, the focusing system 10 of the present invention uses three light emitting elements and three light receiving elements for focusing. On the other hand, when the semiconductor wafer 26 is in a moving state, focusing is performed using four light emitting elements and four light receiving elements. The light beams generated by the first light-emitting element 12 and the second light-emitting element 14 are reflected by the semiconductor wafer 26 on the stage 24, and then transmitted to the first light-receiving element 16 and the second light-receiving element 18. If the light beams are detected by the first light receiving element 16 and the second light receiving element 18, the signal processor 20 in the detecting unit outputs a focal length and transmits the focal length to the control unit. The control unit has a stage 24 and a stage control. The paper size is applicable to Chinese national standards (CNS > A4 size (210 X 297 mm) (please read the precautions on the back before filling this page), θ. 432474 5 3 3 Ο ρ ΐ 1 ', doc / Π Ο 2 Α7 __Β7 ____ V. Description of the invention (1) Device 22' and the stage controller M controls the momentum of the stage 24 according to the signal from the signal processor 20, thereby modulating its momentum. The focal length is used for the exposure process. Figures 3, 4A, and 4B show a focusing method and system according to the present invention, which are used to describe the technical background and its characteristic curve changes. Please refer to Figure 3, Figure 4A and Figure 4B for consumer cooperation of the Ministry of Intellectual Property Bureau. When the incident light 38 is incident from the low refractive index medium 30 to the high refractive index medium 32, the penetration angle of the beam will be Less than the angle of incidence ', the intensity of the transmitted light 42 and the reflected light 40 at this time depends on the angle of incidence of the incident light 38. The incident light 38 is incident on the medium 32 through the medium 30, and the refractive index of the medium 30 is set to about 1.5. The transmitted light will be fT 3 2 'As shown in Figure 4A and Figure 4B, based on the interface 34 existing between the two media, the relationship between the reflectance and the transmittance generated by the two components of the incident light 38 respectively. That is, when When the incident light is divided into two components: the incident light component that enters the interface 34 vertically and the incident light component that enters the interface 34 horizontally, the characteristics of the two incident light components in the media 30 and 32 are analyzed according to the principle of electromagnetic waves. The relationship between the transmittance and transmittance is shown in Figs. 4A and 4B. Here, Fig. 4A shows the reflectance 50 and the transmittance 52 of the incident light component perpendicularly entering the interface 34, and Fig. 4B The plan shows the reflectance 60 and transmittance 62 of the incident light components that enter the interface 34 horizontally. As shown in Figures 3, 4A, and 4B, when the incident angle 44 is about 75 degrees or greater than " At 75 degrees, the reflectance 50 will be higher than the transmittance 52; In addition, when the incident angle 44 is about 80 degrees or greater than 80 degrees, the reflectance 60 will be higher than the transmittance 62. Therefore, when the incident light 38 ， The incidence angle 44 This paper size is applicable to the Chinese standard (CNS) A4 (210 X 297 mm) 432474 5} 3 0 p i Γ. d ο c / () 02 pj _B7_ V. Description of the invention (β) (Please read the notes on the back before filling this page) The range of the reflection of the incident light 38 is maintained at about 75 degrees to 90 degrees The transmission rate will be higher than its transmission rate. As shown in Fig. 5, in the focusing system 10, the incident light 80 and 84 have incident angles 90 and 92, respectively, so that the incident light component entering the interface vertically and the horizontal entering interface The reflectance of the incident light component is higher than the transmittance. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economics Please refer to FIG. 5. According to the present invention, a focusing system 10 with two or more focal lengths can be confirmed, which has a first light emitting element 12 and a second light emitting element 14, The first incident light 80 and the second incident light 84 are generated by the first light-emitting element 12 and the second light-emitting element 14, respectively, and are then irradiated onto the semiconductor wafer 26. At this time, the circuit is constructed on the semiconductor wafer 26 in a stacked manner, in which the first material layer 72 and the second material layer 74 are stacked on the substrate 70 of the semiconductor wafer 26, and the photoresist layer 76 covers The first material layer 72 and the second material layer 74 are disposed on the first material layer 72 and the first material layer 72 and the second material layer 74 have a stepped structure. The light beam is reflected by the surface of the photoresist layer 76 on the semiconductor wafer 26, and the first reflected light 82 and the second reflected light 84 generated by the light beam are adjusted by the focusing system 10. As described above, the first incident light 80 and the second incident light 84 having the incident angles 90 and 92, respectively, can make their reflectance higher than the transmittance. The incident angles such as 92 and 92 can be set by changing the angles of the first light-emitting element 12 and the second light-emitting element 4. For example, the angles of the first light-emitting element 12 and the second light-emitting element 14 can be controlled to make them different from the semiconductor wafer. 26 is at any desired angle 1 and the first light-emitting element 12 and the second light-emitting element 14 have a variable structure. For example, the first light-emitting element 12 and the second light-emitting element 14 can be set so that the first incident angle 90 and the second entry angle corresponding to this paper size are applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) ) 4324T4 ri330pi! '. Diu: / 〇02 Magic _ _____________ B7__I_ 5. Description of the invention (丨 f) The shooting angle 92 is controlled in the range of about 75 degrees to 90 degrees. 6A and 6B illustrate an embodiment of the present invention, a method for confirming a semiconductor wafer focal length and its state in a focusing system for confirming two focal lengths or more by lasers. Schematic of the method. 6A and 6B, according to an embodiment of the present invention, in a focusing system that confirms two or more focal lengths by laser, 'having two or more focal lengths, and There is a single focal length (in other words, horizontal correction) in a specific area of the wafer. During the exposure process, the semiconductor wafer 26 may be exposed in a paused state (as shown in FIG. 6A) or a scanning state (as shown in FIG. 6B). In addition, since the semiconductor wafer 26 is along the X , Y, z, and rotation axes are moved for focusing and horizontal correction, so the focal length needs to be maintained on the same plane to obtain correct horizontal correction. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs as shown in FIG. 6A 'When the semiconductor wafer 26 is at a standstill, it has three focal lengths 100, 102, and UM, and has three focal lengths or more than three focal lengths. normal. The focal length of 104 is perpendicular to the other two focal lengths of 100 and 102, and it is indeed located on the semiconductor wafer 26. Therefore, by using the focal lengths of 100, 102, and 104, stable horizontal calibration can be obtained. Therefore, in the aforementioned focusing system, the light source unit (not shown in the figure) has three light emitting elements, and the detection unit (not shown in the figure) has three light receiving elements, which are respectively different from those of the aforementioned light source unit. Corresponding to the light emitting element. As shown in Figure 6B, when the semiconductor wafer 26 is in the scanning state, this paper size applies the Chinese Family Standard (CNS) A4 specification (210 X 297 mm). Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 432474 5 A7 V. Description of the invention (丨 Z) It has four focal lengths 110, 1 丨 2 '114, and 116, and it is normal to have four or more focal lengths. Among them, the focal lengths 1 丨 4 and 116 are the same as The other two focal lengths Π0 and II2 are vertical and are indeed located on the semiconductor wafer 26, so by using the focal lengths U0, 112, 114, and Π6, etc., stable horizontal correction can be obtained. Therefore, in the aforementioned focusing system, the light source unit (not shown in the figure) has four light-emitting elements, and the detection unit (not shown in the figure) has four light-receiving elements, which are respectively different from the aforementioned light source unit. Corresponding to the light-emitting element in. The light source unit and the detection unit may each have a plurality of light-emitting elements and a plurality of light-receiving elements', so the number of light-emitting elements and light-receiving elements may be adjusted according to demand. The focusing method and system of the present invention project incident light onto a surface at a specific distance, so that the reflectance of the incident light is higher than its transmittance. That is, a focusing method and system that can set the angle of incidence so that the reflectance of incident light depends on its transmittance. By using the focusing method and system of the present invention, relevant information on the surface of the photoresist layer can be obtained, so different focal lengths can be obtained by detecting the stacked structure, which can be reduced to a single fixed focal length. In the calibration system used to confirm two focal lengths or more, the photoresist layer and air used to transmit incident light to the semiconductor wafer can make the incident angle larger than a specific angle due to its refractive index. So you can confirm two specific focal lengths or more than two specific focal lengths. By applying the focusing method and system of the present invention, a fixed focal length can be maintained on a semiconductor wafer having a complex structure. Therefore, during the exposure process, it is possible to avoid the problems of poor focus and horizontal correction, to ensure a good patterning process. In particular, it is confirmed by laser that the velvet has two coke 15… ..._____________________________- ^ This paper size is applicable to the national solid standard (CNS) A4 specification (210 X 297 cm) I l · — ϋ —rn 1 9— (Please read the note on the back first ^: fill in this page) 'SJ__ 4 3 24 7 4 5.130pi j'.doc / (HJ2 pj _B7 V. Description of the invention (multiple) distance or more than two focal lengths In the focusing system of the present invention, for a specific area on a semiconductor wafer having a stacked structure therein, it can be ensured that they have the same focal length. Although the present invention has been disclosed above in a preferred embodiment, it is not intended to limit the present invention. Invention, anyone skilled in this art can make various modifications and retouching without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the scope of the attached patent application. Please read the notes on the back before filling in this page.) Pack -'t /, printed by the employee's consumer cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. The paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm).